# 函数设计
def oddfn(x):
    return x if (x%2==1) else None
myList = [5,10,15,20,25,30]
filter_object = filter(oddfn, myList)
print("奇数列表：", [item for item in filter_object])
print(filter_object, type(filter_object))
print(list(filter_object))

squarelist = map(lambda x:x**2, myList)
print(squarelist, type(squarelist), list(squarelist))